Ce(III) Doped Zr-Based MOFs as Excellent NO2 Adsorbents at Ambient Conditions
Ce(III) Doped Zr-Based MOFs as Excellent NO2 Adsorbents at Ambient Conditions
复制标题
DOI：
10.1021/am402305u
复制
发表时间：
2013-11-13
影响因子：
9.5
通讯作者：
Bandosz, Teresa J.
中科院分区：
文献类型：
--
作者：
Ebrahim, Amani M.;Bandosz, Teresa J.
合成了新型杂化铈改性锆基金属有机骨架（MOFs）。在潮湿或干燥条件下，对接收的材料进行了NO2吸附剂的评价。利用XRD、SEM-EDX、氮气吸附、热分析和FTIR对初始样品和耗尽样品的表面进行了表征，发现Ce+3的加入对Zr-MOF骨架的生长有轻微的影响，并给Zr-MOF引入了新的特征。八面体晶体的形状发生了变化，它们与棒状片状的薄片交织在一起。互连的程度，以及由此形成的杂化MOF的程度，取决于Zr与Ce的比值。表面化学和结构的变化反映在二氧化氮的吸附量上。在这些新材料中存在的窄孔通道增强了在潮湿或干燥条件下的吸附。在干燥条件下，掺ce的MOF吸附NO2的量比未改性的MOF增加了25%以上。Ce-UiO-66暴露于NO2中导致孔隙发育。无论在何种条件下，XRD谱图都表明了这种新型杂化MOF对NO2吸附的稳定性。NO2与MOF的相互作用导致与金属或有机配体相关的硝酸盐和亚硝酸盐的形成。
New hybrid cerium modified zirconium based metal organic frameworks (MOFs) were synthesized. The as-received materials were evaluated as adsorbents of NO2 in either moist or dry conditions. The surface of the initial and exhausted samples was characterized using XRD, SEM-EDX, nitrogen adsorption, thermal analysis, and FTIR It was found that the addition of Ce+3 slightly affects the growth of the framework and introduces new features to Zr-MOF. The shapes of the octahedral crystals are changed, and they are interwoven with rod-flake-like sheets. The extent of the interconnection, and thus the extent of the hybrid MOF formation, depends on the Zr to Ce ratio. The alterations in the surface chemistry and texture are reflected in the amount of NO2 adsorbed. The narrow pore channels present in these new materials enhance adsorption in either moist or dry conditions. The amount of NO2 adsorbed on the Ce-doped MOF increases over 25% in dry conditions in comparison with the unmodified MOF. Exposure of Ce-UiO-66 to NO2 results in a development of porosity. Regardless the conditions, the XRD patterns indicate the stability of this new hybrid MOF upon NO2 adsorption. Interactions of NO2 with MOF result in the formation of nitrate and nitrite species associated either with metals or with organic ligands.